The invention set forth in this specification pertains to new and improved child resistant type dispensing closures.
A dispensing closure is normally considered to consist of a cap adapted to be mounted on or formed integrally with a container and a spout mounted upon the cap so as to be capable of being rotated between a closed position in which an opening to the cap is closed off by the spout and an open position in which the opening is in communication with a passage extending through the spout. Such dispensing closures are more commonly constructed out of a polymer material capable of being temporarily deformed such as polyethylene or polypropylene in such a manner that the parts of such closures can be snapped or popped together. It is well recognized that the constructional details of such closures may vary to significant extents.
The dispensing closure industry has been faced with a significant problem in making dispensing closures of a so-called "child resistant" character in response to a gradually increasing demand for such closures. In generalized terms the expression "child resistant" is employed in the closure field to designate closures which can be opened by the average adult when necessary, but which are sufficiently difficult to open so that there is no reasonable chance of their being opened by a comparatively young child and/or an adult having less than normal capabilities. The need for child resistant dispensing closures has resulted in the development of an extremely large number of different types of such closures. Many of such closures are illustrated in the appropriate patent literature.
Because of economic considerations manufacturers have attempted to provide child resistant closures which are closely related to prior non-child resistant dispensing closures so as to avoid the necessity of making completely new molds or dies for the production of such closures. In other words, manufacturers have desired to modify existing molds for the production of dispensing closures in such a manner that these molds will produce parts which, when assembled together, will provide a dispensing closure of a child resistant nature. An understanding of the present invention is not believed to require a detailed explanation of all of such efforts.
An example of one such effort is indicated in the co-pending U.S. patent application Ser. No. 549,720 which has issued as U.S. Pat. No. 3,957,181. The closure set forth in this patent utilizes a spout which is rotatably mounted in the body of a cap in such a manner that when closed the spout is located in a groove in a position in which it cannot be manually engaged so as to be rotated. In the structure set forth in this patent the spout is provided with a "means" or structure located so as to be capable of being engaged by an implement applied from above the closure so that force exerted through the implement against the spout will rotate the spout to a sufficient extent so that in turn it can be manually engaged to be further rotated to a substantially vertically extending open position. Although structures of this type are utilitarian and are considered to be of a child resistant nature they are believed to have certain inherent drawbacks or limitations.
One of these is that a child playing with such a closure is apt to exert either a vertical force or a force having a predominantly vertical component on such a closure. When this occurs the spout is rotated to a limited degree which is apt to attract the attention of a child so as to cause the child to further investigate the structure by manipulating the spout. If this should happen, there is danger of the spout being opened. Further, structures as are set forth in the aforenoted patent have been designed so as to accommodate an extending enlargement on the spout within a cavity within the cap. Although such a structure is useable it does not effectively preclude air from the passage within the spout when the spout is in a closed position.
The reasonable exclusion of air from a spout in a dispensing closure when the spout is in a closed position is considered to be desirable for several reasons. Such exclusion will tend to minimize contamination within the interior of the spout. Further, dispensing closures are apt to be utilized with somewhat viscous materials which will not flow readily. Such materials may be held within the spout as the spout is rotated from an open to a closed position. The ends of the spout should be reasonably excluded from the ambient air in order to prevent any such material from drying out within the spout and/or from gradually flowing from the spout if the spout is in a non-horizontal position when closed.